Superficial Siderosis Signals Amyloid Angiopathy

Cortical superficial siderosis (CSS) describes hemosiderin deposition in subpial layers over the cerebral convexities. CSS is thought to be indicative of cerebral amyloid angiopathy (CAA) and is associated with increased risk for intracerebral hemorrhage (ICH). To test this hypothesis, researchers examined 257 consecutive patients in Korea with clinically diagnosed subcortical vascular cognitive impairment (SVCI) or Alzheimer disease–related cognitive impairment (ADCI), performing structural brain magnetic resonance imaging (MRI) and amyloid imaging with Pittsburgh compound B (PIB-PET).

Of 232 patients with SVCI or PIB⁺ ADCI, 12 patients (6 of 90 with ADCI; 6 of 142 with SVCI) had evidence of CSS according to raters blinded to diagnosis, wit…